​Presidio of San Francisco (September 14, 2009) -- A one of a kind building at the Presidio is getting a one of a kind repair. Presidio Trust carpenters are restoring the exterior walls of the park’s historic Log Cabin--replacing and repairing selected logs, replacing the “chinking” (the material between the logs) and staining the logs to match the cabin’s original finish. The work, which began in mid-June, is expected to be completed this fall.

“We’re very proud to be able to do this unique restoration project with Trust crews,” says Christina Wallace, architectural conservator for the Trust. “This is such a specialized repair—there aren’t a whole lot of log cabins—that we were excited to do it ourselves.”

The Trust’s carpenters, all of whom have been specially trained in log repair and restoration, salvaged about 50 Monterey cypress logs, the same type used by the Army when it built the cabin in 1937, from the reforestation project at the Julius Kahn playground in 2007. Since then, the logs have been seasoning in a building in Fort Scott—drying out to reach the proper moisture content for the project. The original logs used by the Army were also harvested from the Presidio forest.

Carpenters began by “refacing” the most heavily damaged logs on the cabin’s western edge. They’ll shave off the log’s face or arc, replacing it with a similarly cut section of a new log. The newer logs have a yellowish hue to them, and are much brighter than the original logs. However, they weather quickly and before long blend seamlessly in to the cabin’s wall—leaving little trace of the repair.

Once the log repair is complete, workers will begin removing the original chinking from between the logs. As was common at the time, the original chinking material contained horse hair. Later, the cabin was coated with an acrylic sealant. Rather than keep moisture out however, the sealant actually ate away at the original material. As it dried out and shrank, it pulled the horse-hair with it, allowing water in. Crews are replacing the deteriorated chinking with a modern cement-like mix.

Finally, the logs will be freshly stained, recreating the cabin’s original appearance.

The only building in the Presidio built in the increasingly rare “rustic” style, the cabin was originally a non-commissioned officers’ club. Over the years it has served as a mess hall, community center, and now a special events venue. Situated in the historic Fort Scott district, the cabin has been battered by decades of exposure to one of the Presidio’s harshest climates. The rain, fog, and sunlight have taken their toll, leaving the logs with a washed out appearance.

“The repairs will, with luck, help the cabin to stand strong for the next 70 years” says Wallace. “It won’t lose its beloved rustic look.”

The Presidio Trust was established by the United States Congress in 1996 to oversee the Presidio of San Francisco, an urban national park located at the base of the Golden Gate Bridge. The 1,500-acre site contains expansive open space and spectacular views, a 300-acre historic forest, and rare and endangered plants and wildlife. It also comprises nearly 6 million square feet of buildings, including 469 historic structures that contribute to its status as a National Historic Landmark District.